Locking tweezers



Sept. 3, 1968 e. L. HALL LOCKING TWEEZERS Filed Dec. 9, 1966 IN VENTOR.

PM .0: i '5 a United States Patent 3,399,583 LOCKING TWEEZERS Gordon Lance Hall, Woodstock, Conn.

(Box 72, Pomfret, Conn. 06258) Filed Dec. 9, 1966, Ser. No. 600,665 2 Claims. (CI. 8143) ABSTRACT OF THE DISCLOSURE A modification of vise-tweezers incorporating a sliding sleeve on one arm with an attached loop which encircles the opposing arm. When the sleeve is pushed toward the tips the loop engages a sloping protrusion, exerting a pressure on the points to close them and to constrain them from moving apart, thus maintaining a grip on any object held between the tips of the arms.

This invention relates generally to tweezers which have a resilient pair of opposing arms, and are intended to be used in the fingers of the human hand, and especially to that type of such tweezers as have incorporated a device for locking the two arms in such a condition that a small object held between two points of the arms will remain so locked when the pressure of the fingers on the arms has been released.

One object of this invention is to provide a tweezer locking actuator in such a position, and of such construction that the grip and application of pressure by the fingers will not be inconvenienced, and at the same time the actuator will be in the most convenient possible position. When the tweezers are held in the normal position for grasping an object between the tips of the arms it is most convenient if the lock actuator is in a position under either the thumb or the middle finger, so that it is unnecessary to change the grip of the fingers in order to engage or disengage the locking device by a sliding motion of the thumb or middle finger, whichever is on the lock actuator. Such a motion toward the tips of the arms will engage the locking device, and the reverse motion toward the stem of the tweezers will disengage it. The tightness of the grip of the tips on the held object can be delicately regulated by the amount of force used in this sliding motion.

A second object of this invention is to provide tweezers in which the shape of each arm is approximately a half round so that when the arms are pressed toward each other to the position in which an object is held between the tips the total cross-section shape of the tweezers in the area in which they are held between the thumb and fingers is an approximately round. The nearly round shape of the locked tweezers has the advantage of permitting them to be easily rolled between the thumb and fingers so that a held object being inspected or positioned for assembly can be turned to any angle without a major change of the grip or awkward positioning of the wrist. Tweezers with flat or only slightly rounded arms cannot be rolled between the thumb and fingers without danger of the arms side-slipping so that the held object is inadvertently released.

A third feature of this invention is that its structural features are of such character that the arms and stem can be made of a strong, resilient plastic. The advantages of the use of this material are:

(a) lightness in weight for ease of handling;

(b) the material is a non-conductor and use in live electric circuits would be less liable to induce short circuits by inadvertent contacts.

Tweezers made of ferrous metal with arms of similar shape and of a size convenient for the hand would be inconveniently heavy, or inconveniently small in cross-section.

A fourth object of the invention is to provide tweezers which can be conveniently rotated in the fingers when held at the stem for purposes of inspecting or examining small objects.

With these and other objectives definitely in view, this invention consists in the novel combination and arrangement of elements as will be hereinafter fully described in the specification, particularly pointed out in the claims, and illustrated in the drawings that form a material part of this disclosure, and in which:

FIGURE 1 is a longitudinal elevation of the invention;

FIGURE 2 is an enlarged perspective view of that part of the invention between the lines 22 of FIGURE 1;

FIGURE 3 is an enlarged cross-section taken on the line 3-3 of FIGURE 1.

The components of my invention and their manner of functioning are as follows:

Referring to FIGURE 1 in which the entire invention is shown, it can be seen that the tweezers are composed of two opposing arms 10 and 11, which are integral with or firmly attached to a common stem. On one of these arms is a component 12, which will be hereinafter referred to as the sliding sleeve. This component is made of thin metal and is so shaped as to envelop the arm 10, yet is easily slidable thereon, and is so located on the arm, and of such a length, that when the tweezers are picked up and held for use in the human hand, either the thumb or the middle finger rest on it as pressure is applied to bring the two arms 10 and 11 toward each other to grasp an object at their tips. When the opposing tips of the arms 10 and 11 are pressed together on an object with sufficient force between the fingers and thumb to enable the part to be lifted, either the thumb or the middle finger, whichever is resting on the sliding sleeve 12, can be moved toward the tips where the part is held, and the sliding sleeve will move in that direction, thus engaging the locking device.

Attached to and integral with the sliding sleeve is a loop of metal 13 which completely encloses both of the arms 10 and 11 and will be hereinafter referred to as the pressure-retaining loop. Thus when the sliding sleeve 12 moves forward the pressure-retaining loop 13 moves to contact the component 14, which is a firmly attached or integral sloping protrusion from the outside of the arm 11, which arm opposes arm 10 on which the sliding sleeve 12 operates. This sloping protrusion will hereinafter be referred to as the pressure-retaining slide. Thus when the sliding sleeve is moved forward (toward the tips) the pressure-retaining loop 13 moves forward and will contact some point on the pressure-retaining slide 14. When this occurs the pressure of the fingers on the arms -10 and 11 can be relaxed, and the arms 10 and 11 will remain locked in a position which will maintain tension on an object held between their tips. The pressure on the held object will be regulated by the pressure used to press the pressure-retaining loop up the slope of the pressureretaining slide.

By reference to FIGURE 3 it can be seen that the member component 13, which envelops both of the arms of the tweezers, constrains the movement of the arm 11 from moving out of alignment with the arm 10. Any lateral motion of either arm in relation to the opposing arm would tend to rotate a small object held between the tips of the arms 10 and 11, and the change in the relative direction of the opposing pressures could cause the held object to drop from the grasp of the tips. This feature of the maintenance of the alignment of the arms 10 and 11 is also reinforced by the V-shaped conformation of the pressure-retaining loop 13 in its contact with the pressureretaining slide 14.

3 l i 4 It is understood that minor variation from the form of tending from the outer side of the arm opposing that the invention disclosed herein may be made without deon which the slide is mounted in such a position that parture from the spirit and scope of the invention, and when the slidable component with its attached loop that the specification and drawing are to be considered as moves toward the tips of the tweezers said protrumerely illustrative rather than limiting. 5 sion will be impinged on by the said loop, thus act- I claim: ing as a lock which can hold the arms in a condition 1. Tweezers having a locking device to hold an object f opposing t nsion, firmly between the p of the tWeeZer arms after the P 2. Apparatus as claimed in claim 1, wherein said arms 0f the fingers and thumb has been released, 1 form an approximate round when pressed together, so Pflslfig! 10 that the entire apparatus, when locked on an object, can (a) a stefni be easily and smoothly rotated between the thumb and (b) a pair of resilient arms extending from said stem; fingers of one hand (0) a slidable component mounted on one arm in a position so as to be in contact with the holding digits References Cited of the hand when the tweezers are in the normal 15 position for picking up an object; UNITED STATES PATENTS (d) a rigid loop rigidly attached to the outer end of 1,269,321 6/1918 Schwarz 81-43 said slidable component, which loop encloses the 1,315,303 9/1919 A l i 31 43 arms of the tweezers; and (e) a sloping boss or protrusion attached to and ex- 20 OTHELL M. SIMPSON, Primary Examiner. 

